Flow regulating valve



une 2, w33. M. H. GROVE FLow REGULATING VALVE Filed Jan. 6, 1932 2Sheets-Sheet 1 /VAew/v H. GROVE. BY Mrk-fgov A TTORNEYS.

June 2, 1936. M. H. GROVE 2,042,781

FLOW REGULATING VALVE 2 Sheets-Sheet 2 Filed Jan. 6, 1932 INVENTOR.Haar/N H lan/e.

A TTORNEYS.

Patented June 2, 19?'6 UNITED STATES PATENT oFElcE 1 Claim.

My invention relates to improvements in regulating valves, and itconsists of the combinations, constructions and arrangements hereinafterdescribed and claimed.

I am aware of pressure-regulating valves in which fluid pressure to becontrolled acts on one side of a diaphragm and a spring of xed tensionor a weight acts upon the other side of the dia-v the source of power tomove the valve in place of the spring or weight, with the result thatthe movement is almost instantaneous, since there is no inertia to beovercome other than the weight of the moving parts. The result attainedis practically a smooth ilow, which is really the object to be attainedin most applications rather than pressure regulation.

One of the `principal objects of my invention is to provide a. device ofthe type described, in which novel means is provided for taking care ofvariations in temperature, so that the valve will operate as desiredregardless of these changes. I also provide means for automaticallycompensating for the enlarging of the capacity of the controlcompartment, whereby the control valve operated by a diaphragm forming apart of the control compartment will be moved with an equal forcethroughout its entire distance, even though the diaphragm in flexing,enlarges the capacity ofk the control compartment and thus reduces thepressure within the compartment. y

Still another object is to provide a controlled valve with all thedesirable smooth flow characteristics of a balanced valve, and, at thesame time, with identical tight shut-E features of a single bevel-seatedvalve.

Still another object is to provide means for permitting fluid pressureon one side of the operating diaphragm of this controlled valve to passinto the compartment disposed on the other side of the diaphragm andthus cause the valve to open without sudden jerk and at the same timecause it to move toward the closed position more rapidly.

Other objects and advantages will appear in (Cl. SI1-12) the followingspecication, and the novel features I of the device will be particularlypointed out in the appended claim.

My invention is illustrated in the accompanying drawings forming a partof this application, in which Figure l is a sectional schematic view ofthe entire device;

Figure 2 is an enlarged sectional view of a portion of the controlvalve;

Figure 3 is a top plan view of Figure 2;

Figure 4 is an enlarged sectional view of the control valve; and

Figure 5 is an end elevation of Figure 4.

In carrying out my invention, I provide a control valve, indicatedgenerally at A, and a controlled valve, indicated generally at B, A highpressure gas-conveying pipe I, (see Figure 1), communicates with aninlet 2 of the controlled valve, while a low pressure conveying pipe 3communicates with an outlet 4 of the controlled valve.

Itis best to describe ilrst the path taken by the high pressure gaspassing from pipe I and then to show how this controls the pressure ofthe low pressure gas, regardless of the amount of gas be- I ingwithdrawn from the low pressure line 3.

The valve B has a head 5 divided into two compartments, or chambers 6and 1, by a diaphragm 8. A conduit 9 conveys high pressure gas from theinlet 2 to a illter I0, and a second conduit II conveys the highpressure gas from the lter III to a passage I2 in the head 5. An orificeI3 permits flow of high pressure gas from the passage I2 into thechamber 1, while a second orice I4 permits high pressure gas to enterthe compartment 6. It will be seen that high pressure.

gas will fill the compartments 6 and 1, and as long as gas does notescape from either compartment faster than it can enter through theoriilces I3 and I4, there will be a balancing of forces on both sides ofthe diaphragm 8 to move the valve stern I5, which is fastened to thediaphragm 8.

The valve stem I5 passes through a diaphragm I6 that separates thecompartment 1 from the inlet 2. A guide plate I1 has openings I8 thereinforpermitting the high pressure in the inlet 2 to force against one sideof the diaphragm I6, and high pressure in the chamber 1 to force againstthe otherI side of the diaphragm. There will therefore normally be abalancing of the forces on both sides of the diaphragm I6.

A partition 23 acts as a guide for the lower portion of the valve stemI5, and this partition has openings 24 therein for leading the' highpressure gas into a compartment 25 closed by a diaphragm 26. On theopposite sides of this diaphragm, in a compartment 68, is the lowpressure gas, since this compartment is connected with the low pressurepipe 3 by a passage 61. Thus, we

have the pressure differential between the highv and low pressure actingon the diaphragm 26 to keep the valve closed.

'Ihe diaphragm 8, 4 through the valve stem l5, actuates a double valve|9 and 20. The valves |9 and 20 are normally seated on valve seats 2|and 22, and the high pressure gas in the inlet 2 will exert a force onthe top of they valve I9 and on the bottom of the valve 20, sofas tobalance the forces.

Communication is established between the compartment 6 of the valve Bandthe control. valve A. A passage 21 in the head 5 places thecompartment 6 in communication with a conduit 28. The control valve Ahas a conduit 29 communieating with the conduit 28, and a valve orifice30 is carried by the conduit 29 and is normally closed by a movablevalve seatf3l. Thus far, I have described the various passageways andcompartments occupied by the high pressure gas. I will now describe thecontrol compartment and then will set forth how this compartment keepsthe pressure of. the gas in the low pressure line 3 at a pressure todeliver equal amounts of gas by weight from the pipe 3, regardless oftemperature change.

The control valve has a control compartment 32 therein, which isplaced/n communication with the conduit '28 by means of a passage 33,this passage being controlled by needle valves 34 and 35. 'I'he operatoropens the needle valves so as to allow any desired pressure to be builtup in the control compartment 32, whereupon, needle valves 34 and 35 areclosed. The pressure in the control compartment 32 is less than thepressure in the conduit 28. If it is desired to lessen the pressure inthe control compartment, a needle valve- 36 is opened and permits flowthrough an exhaust passage 31`to theatmosphere. Pressure gauges, notshown, may be used on the control compartment32 for indicating thispressure.`

One wall 38 of the compartment 32 is perforated, as at 39, and permitsthe gas pressure in the compartment to exert a force on a diaphragm 40that separates the control compartment 32 from-a compartment 4|.

A'plate 42 yseparates the diaphragm 40 from a second diaphragm 43, and avalve stem 44 is secured to the plate. This valve stem 44 passes throughthe compartment 4|, thence through a partition 45, and is provided witha yoke 46 at its lower end, this yoke carrying the valve 'seat 3|. Aspring 41 normallykeeps the stem 44 raised, and faids the gas pressureon diaphragm 43 in keeping the valve 30 normally closed. The provisionof two diaphragms 40 and 43 permits the stem 44 to be connected to thediaphragm 40 without puncturing it.

' Assume that a pressure of two ounces is trapped in the controlcompartment 32 and that a pressure of 100 pounds is exerted by the gasin the pipe and in the conduit 28. There will be no pressure in thecompartment 4| until the pressure of two ounces is built up in the lowpressure line 3, because the compartment 4| communicates with the lowpressure line by means of a conduit 48.` The pressure of the gas in thecompartment 32 will therefor move the diaphragms 40 and 43 downwardly,and this will cause the valve stem 44 to move the valve seat 3| awayfrom the valve 39. Immediately, the gas under a higher pressure; i. e.100 pounds, will ow into a compartment 49 and then will be carried by apassageway 50 into a compartment 5| that envelopes the controlcompartment 32. From here, the gas will enter a passage 52, and thenceto a pipe 53 that communicates with the low pressure pipe 3. The gaswill flow until the pressure in the low pressure pipe 3 and likewise thepressure in the compartment 49, sinceA compartment 49 and pipe 3 areconnected by passage 48, has,

risen in pressure to slightly more than two ounces, and the diaphragms4U and 43 will move upwardly since the pressure in the compartment 4| issufficient to overcome the pressure in the control chamber 32. Thus, thediaphragms 40 and 43 will lift the valve Astern 44y and close the valve39 and further flow will cease.

Before proceeding further with the operation of the device, it is bestto set forth how the temperature of the gas in the control compartmentis controlled. The gas, in passing through the valve orifice 30, isreduced in pressure since it is allowed to expand in the compartment 49,and

ithis reduced pressure will closely approximate the .,perature 4of thegas in the control compartment 32 the same as the gas in the lowpressure pipe, since this compartment is almost entirely surrounded bylow pressure gas, and the heat transfer from one compartment to theother is accomplished by conduction. -The gas in the control compartment32 will never be at a different temperature from the gas in the lowpressure pipe 3.

If, for example, the temperature of the gas in the control compartment32 were allowed to rise above that of the gas in the pipe 3, such as maybe caused by a rise in the temperature of the surrounding atmosphere, wewould have a corresponding rise in pressure, since the volume of thischamber is constant, and this, in turn, would cause a rise in pressurein the pipe 3. The rise in pressure in the pipe 3 would take place inorder to move the diaphragm 40 upward and close the valve 3| f It isobvious, therefore, that we must have means of controlling thetemperature of the gas in the control compartment 32 if we wish to havethe same amount of gas by weight fiow in the pipe 3, regardless oftemperature.

In this particular device, in which we control the flow of a fluid suchas illuminating gas where quantity of gas flowing is desired, weautomatically raise the pressure of the gas in the low pressure pipe 3to compensate for a temperature rise. Vice versa, we lower the pressureof the gas in the pipe 3 if the temperature of the gas drops. This isdesirable since the gas is less dense if the temperature is high than ifthe temperature is low.

If, for example, my device were controlling the flow of gas passingthrough a meter, and the gas were subject to changes in temperature, mydevice would automatically adjust the pressure of the flowing gas suchthat the meter would record the correct quantity of gas passing throughthe meter. With an ordinary pressure regulator,

it woulvdbe necessary to record the temperature of the gas and correctthe meter readings- Itis desirable, in this manner, to `control the flowof any fluid where quantity control is desired.

However, in controlling the flow of steam, compressed air, etc., 'wherea constant pressure control is desired (since it is energy stored in thegas by its compressed state which is used rather than the iiuid itself)I must have means of maintaining a constant pressure in the controlchamber. I accomplish this by closing off passages 50 and 52 andremoving the plug 49. Thus, Iy

will not subject `the gas in the chamber 32 to the pressure changes thatoccur in the pipe 3.

However, I must further provide against any change of temperature thatmight be induced by the gas in the chamber 4I or any outside cause suchas atmospheric. I accomplish this by providing a heating element I inthe compartment 5I that will automatically maintain the temperature ofthe gas in the chamber 32 above that of any temperature it may besubjected to from any outside source.

I provide novel means for automatically compensating for the enlargingof the control compartment so that the same force will be exerted on thevalve stemv 44 during the entire movement of the stem. Fulcrum edges 55,(see Figure 2), are carried by the partition 45, and levers 56 arepivoted on the edges. Links 51 extend from the levers 56 and fulcrum innotches 56 on a nut 59 carried by the valve stem 44. Figure 3 shows howthe tops of the levers 56 are fulcrumed on knife edges 60 carried bycup-shaped members 6|. Springs 62 extend between the members 6I andsupports 63. The supports, in turn, are carried by rods 64. If desired,the rods can be supported in bearings (not shown).

The links 51 will exert a certain downward force on the valve stern 44when the -links a-re in the position shown in Figure 2. If the volume ofthe compartment 32 increases in size, the pressure will decrease, andthis pressure decreases as the valve stem 44 moves downwardly. Thedownward movement of the valve stem 44 increases the angle of the links51, and, therefore, the springs 62 will cause the links to exert agreater downward force as the links swing through an angle. Theforce ofthe springs 62 may be adjusted so that the gradual increasing of thedownward force of the links on the valve stem will equal the gradualdecreasing of the force of the gas pressure in the compartment 32 on thediaphragm 4U. In this way, the mechanism shown in Figures 2 and 3automatically compensates for the decrease in pressure in thecompartment 32.

The compartments 6 and 1 are placed in communication by a passage 65 andan orifice 66 for a purpose hereinafter described.

If the amount of gas withdrawn from the pipe 3 were more than theorifices I3, I4 and 66 could handle, we would have a pressure drop inthe compartments 6 and 1. These orifices are of such size that thepressure drop in the compartment 6 will be greater than the pressuredrop in compartment 1.

When the differential pressure acting on the diaphragm 8 is sufficientto overcome the force exerted by the diaphragm 26 and the weight of themoving parts of the valve, valves I9 and 20 will move upwardly and gaswill flow from the inlet 2 into the low pressure pipe 3. The provisionof the orifice 66 causes the valves I9 and to lag slightly in opening.This prevents chattering, and the valves will open to the desiredamount.

As soon as pressure in the low pressure pipe 3 exceeds two ounces, thevalve 30 will be shut ofi' and will stop the flow out of `thecompartments 6 and 1. The pressure will then equalize rapidly in thecompartments 6 and 1, due to the orice 66 while gas is flowing into themthrough the orices I3 and I4, and the diaphragm 26 will shut off thevalve B more quickly than if the orice-66 were not provided. v

I have so far described the forces which operate l0 my valve. In actualoperation, the valve 3I is constantly and rapidly opening and closing tomaintain the proper differential pressure acting on the diaphragm 6 suchthat the valves I9 and 20 will maintain the proper opening to keep the15 quantity of gas passing these valves at the correct amount tomaintain an even pressure of two ounces in the pipe 3.

It should be noted that any regulating valve is subject to forces whichmove the valve out of 20 the correct position at any given instant, suchas constantly changing pressure in the compartment 2, eddy currentsflowing past the valve which act upon the valve, etc. The valve must beconstantly adjusting its position to maintain an even flow. My principlepermits this adjustment very rapidly.

However, there is another factor which must be considered; i. e. anybevel-seated or poppet valve must have a seat ring, and each time thevalve moves off its seat, there is the force of the pressure on thisarea suddenly acting on the valve to open it.

This force suddenly acts upon a partiallyopened valve and is added tothe force that is sufflcient to open the valve, with a result that theadded force of the flowing gas tends to cause the valve to move fartheropen than is necessary. To overcome this, I have held in check thepressuredifferential between the chambers 6 and 1 40 by permitting apredetermined flow of gas from the chamber 1 into the chamber 6 when thepressure is reduced in the chamber 6. 'I'his orifice 66 also allows thediaphragm 8 to be relieved of its differential pressure more quicklywhen the valve 30 is closed, with a result that more rapid applicationof closing force is applied on the valve B.

It should be noted that a single seated valve has very uneven owcharacteristics, but has about the correct shut-oil' characteristics. Ihave 50 employed a so-called balanced valve in valve B with thedesirable flow characteristics of this type of valve, but by usingcomposition seats on the valves I9 and 26 and by using the diaphragm 26,

I have secured the advantages of both the singleseated valve and thebalanced valve.

It should be noted that the lower side of the diaphragm 26 could beexposed to the atmosphere with the same effect as is shown if only onelow pressure is desired, and the area of the diaphragm 26 is consideredin the design in accounting for the added closing effect of the lowpressure on the valve B. I

The provision of the orifice 66 not only causes a lag in the valveopening movement of the diaphragm 8 when fluid is withdrawn from thechamber 6, but it also permits the more rapid equalization of pressuresin the chambers 6 and 1 when fluid is stopped from being withdrawn 70from the chamber 6, with a result that the pressures in the chambers 6and 1 will balance before they, will equal that in the high pressureline, and the high pressure on the diaphragm 26 will then instantlyclose the valves I9 and 20, after which 75 the pressures in the chambers6 and 1 will build up to normal.

It will be seen from the description that I providea device that willmaintain a predetermined pressure at a predetermined temperature in alow pressure pipe and'automatically compensate for temperature changesby pressure changes.

While I have shown only the preferred form of my invention, it shouldbeunderstood that various changes or modifications may be made within thescope of the appended claim without departing from the spirit of theinvention.

I claim:

In a, control valve, a casing, a dome-shaped member having a ange withinlet and outlet passages in the flange leading to the interior of themember, needle valves for the passages, a diaphragm closing thedome-shaped member, a valve stem supporting member disposed adjacent tothe diaphragm, a second diaphragm placed on the other side of thesupporting member, and a valve stem extending through the seconddiaphragm and being secured to the supporting member, said diaphragmsand dome-shaped member being secured to the casing.

f MARVIN HENRY GROVE.

